Firearms utilize high pressure exhaust gasses to accelerate a projectile such as a bullet. Firearm silencers (hereafter referred to as “suppressors”) are typically added to the muzzle (exhaust) of a firearm to capture the high pressure exhaust gasses of a given firearm. These high pressure exhaust gasses are the product of burning nitrocellulose and possess significant energy that is used to accelerate the projectile. The typical exhaust gas pressure of a rifle cartridge in a full length barrel may be in the range of 7-10 Ksi. A short barreled rifle may have exhaust gas pressures in the 10-20 Ksi range. Moving at supersonic speeds through the bore, the exhaust gasses provide the energy to launch the projectile and also result in the emanation of high-decibel noises typically associated with the discharge of firearms. When in action, firearm suppressors lower the kinetic energy and pressure of the propellant gasses and thereby reduce the decibel level of the resultant noises.
Firearms suppressors are mechanical pressure reduction devices that contain a center through-hole to allow passage of the projectile. Suppressor design(s) utilize static geometry to induce pressure loss across the device by means that may include rapid expansion and contraction, minor losses related to inlet and outlet geometry, and induced pressure differential to divert linear flow.
Suppressors can be thought of as “in-line” pressure reduction devices that capture and release the high pressure gasses over a time (T). Typical suppressor design approaches used to optimize firearms noise reduction include maximizing internal volume, and providing a baffled or “tortured” pathway for propellant gas egress. Each of these approaches must be balanced against the need for clear egress of the projectile, market demand for small overall suppressor size, adverse impacts on the firearms performance, and constraints related to the firearms original mechanical design.
Baffle structures within a suppressor provide the “tortured” pathways which act to restrain the flow of propellant gasses and thereby reduce the energy signature of said gasses. As a result of this function the baffle structures in a suppressor are typically the portion of a suppressor that absorbs the most heat from propellant gasses during firing. The “mirage” effect is distortion of the sight picture caused by hot air rising off of the hot suppressor directly in front of the aiming optic on the firearm. The “mirage” effect is a well know negative aspect of using a suppressor with a firearm, and is often mitigated by wrapping the suppressor in an insulating wrap.
The inventors herein have recognized significant issues, such as the “mirage” effect, related to excess heat build-up that may arise due to the use of a suppressor on a firearm. In the current invention a plurality of baffled gas exhaust tubes, each of which reside in their own internal tube, are employed to reduce the pressure of the propellant gasses. To mitigate the issues related to excess heat build-up the baffled exhaust tubes are positioned such that the tubes are not tangent with (touching) an interior surface of the outer wall or each other. The plurality of baffled exhaust gas tubes are instead contained within fluted spiral structures that follow a rifling pattern about a central axis along the longitudinal length of the suppressor's inner body wall. In at least one example, these tubes may be non-coaxial tubes relative to the central axis of the suppressor. Moreover, these tubes may be spaced away from an interior surface of the suppressor's inner body wall and these tubes may not contact the interior surface of the suppressor's inner body wall.
The inventors herein have recognized that this positioning maximizes the surface area of the plurality of baffled exhaust gas tubes inside the suppressor body to maximize thermal transmission between the hot exhaust gases and the suppressor body. This positioning further helps to more evenly distribute the heat energy of the hot exhaust gases to the interior structures of the suppressor body such that “hot spots” are minimized. In addition, the positioning minimizes the thermal transmission between the internal baffled exhaust gas tubes and the outer wall; a lumen defined by the area between the inner surface of the suppressors' outer wall and the outer walls of the baffled exhaust gas tubes creates a thermal buffer. As a result, thermal transmission from the high heat area of the baffled exhaust tubes to the outside wall is minimized. By delaying the heating of the suppressors' outer wall, the “mirage” effect to the shooter is delayed, allowing the operator to shoot more cartridges before the “mirage” effect occludes the view through the optic.
Autoloading firearms, both semi-automatic and automatic, are designed to utilize a portion of the waste exhaust gasses to operate the mechanical action of the firearms. When in operation the mechanical action of the firearm automatically ejects the spent cartridge case and emplaces a new cartridge case into the chamber of the firearms barrel. One typical autoloading design taps and utilizes exhaust gasses from a point along the firearms barrel. The tapped gasses provide pressure against the face of a piston, which in turn triggers the mechanical autoloading action of the firearm. The energy of the tapped exhaust gasses supplies the work required to operate the mechanical piston of the firearm enabling rapid cycling of cartridges.
The inventors herein have recognized significant issues arising when suppressors are employed on autoloading firearms. As an example, use of a suppressor may result in sustained elevated internal pressures which result in transmission of excess work energy to the piston during the course of operation. When use of a suppressor results in such a build-up of pressure in the firearms chamber over an extended time (T), the excess work energy may lead to opening of the breech (chamber) sooner than is supported by the original firearms design. Therefore, as recognized by the inventors herein, overcoming this issue requires achieving the desired pressure loss (ΔP) over an abbreviated time (T) such that the internal pressure returns below the pressure threshold of the piston before firing of the subsequent cartridge. As a second example, use of a suppressor on autoloading firearms may result in excess venting of exhaust gasses at the rear of the weapon in the direction of the operator. Excess venting of exhaust gasses at the rear of the weapon is undesirable as the gasses may contain toxic substances, and the particulate matter in the gasses may foul the weapons chamber.
In one embodiment, the issues described above may be addressed by a suppressor comprising a geometric baffle system and further comprising an auxiliary system of a plurality of baffled exhaust gas tubes that may achieve the desired pressure loss (ΔP) over an abbreviated time period (ΔT). The suppressor may be of a unitary design generated by 3D printing. In another embodiment, the issues described above may be addressed by a suppressor comprising a plurality of exhaust vents that efficiently direct the exhaust gasses outward through the front of the suppressor and away from the operator and the firearm. By reducing the time required for the internal pressure of suppressor, chamber, and barrel to return to ambient pressure conditions, by time Tx, mechanical malfunction of the autoloading mechanism may be avoided. Further, reducing the internal pressure in the suppressor over an abbreviated time period reduces the pressure inside the barrel and chamber, thereby eliminating excess venting of exhaust gasses at the rear of the firearm in the direction of the operator.
The auxiliary baffled exhaust tubes may exit in any direction. Exiting out the front of the suppressor was chosen as this was the direction opposite the operator. There could be a scenario where this is suboptimal and other directions would be considered. For example, it may be desirable to have the exhaust gasses exit out of the side of the suppressor or on only one side to minimize exhaust gas occluding sensors on remote weapon platforms.
In this way, the firearm suppressor may be operable on any type of autoloading firearms, including but not limited to machine gun applications, without adversely affecting mechanical operations according to the original firearms design. Further, the firearm suppressor may be operable without adversely impacting the safety or performance of the operator. The utility of the suppressor may therefore be extended and more fully realized. Other elements of the disclosed embodiments of the present subject matter are provided in detail herein.
In another embodiment, the suppressor may be operatively configured to be attached to a firearm. The suppressor may include a tubular housing body defining a longitudinal or central axis, wherein the baffle sections and further wherein the spiral fluting sections and further wherein the auxiliary system of baffled exhaust gas tubes of the suppressor are integrated and encased within a parent tubular housing component. In this way, the interior baffle section(s) may be surrounded by a housing such that the efficiency and efficacy of the suppressor are maintained.
The tubular housing body may further comprise a projectile entrance portion and a projectile exit portion disposed at a longitudinally rearward region and a longitudinally forward region, respectively. The rearward end of the suppressor may have an opening sufficiently large enough to permit passage of at least a portion of a firearm barrel, where the suppressor may attach via connectable interaction devices such as interlacing threads.
It should be understood that the summary above is provided to introduce in simplified form, a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the subject matter. Furthermore, the disclosed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.
The above drawings are to scale, although other relative dimensions may be used, if desired. The drawings may depict components directly touching one another and in direct contact with one another and/or adjacent to one another, although such positional relationships may be modified, if desired. Further, the drawings may show components spaced away from one another without intervening components therebetween, although such relationships again, could be modified, if desired.